X-Git-Url: https://thelambdalab.xyz/gitweb/index.cgi?a=blobdiff_plain;f=src%2Fscheme-library.scm;h=2c6146eb57a80948261ef3a552e14188416c1f58;hb=5eea24f47ad60b69af59a76c7285ec232c29009c;hp=85580fdb65540e5d45e05175bd6cfb4ddf92487e;hpb=3055ae2e3d57ec91a4187a6c5cf8f05357d60810;p=scheme.forth.jl.git diff --git a/src/scheme-library.scm b/src/scheme-library.scm index 85580fd..2c6146e 100644 --- a/src/scheme-library.scm +++ b/src/scheme-library.scm @@ -12,8 +12,34 @@ (define (cadr l) (car (cdr l))) (define (cdar l) (cdr (car l))) (define (cddr l) (cdr (cdr l))) +(define (caaar l) (car (car (car l)))) +(define (caadr l) (car (car (cdr l)))) (define (cadar l) (car (cdr (car l)))) +(define (caddr l) (car (cdr (cdr l)))) +(define (cdaar l) (cdr (car (car l)))) +(define (cdadr l) (cdr (car (cdr l)))) +(define (cddar l) (cdr (cdr (car l)))) +(define (cdddr l) (cdr (cdr (cdr l)))) +(define (cadddr l) (car (cdr (cdr (cdr l))))) +;; FUNCTIONAL PROGRAMMING + +(define (fold-left proc init l) + (if (null? l) + init + (fold-left proc (proc init (car l)) (cdr l)))) + +(define (reduce-left proc init l) + (if (null? l) + init + (if (null? (cdr l)) + (car l) + (fold-left proc (proc (car l) (car (cdr l))) (cdr (cdr l)))))) + +(define (map proc l) + (if (null? l) + '() + (cons (proc (car l)) (map proc (cdr l))))) ;; NUMBERS @@ -118,18 +144,6 @@ (define (null? arg) (eq? arg '())) -(define (fold-left proc init l) - (if (null? l) - init - (fold-left proc (proc init (car l)) (cdr l)))) - -(define (reduce-left proc init l) - (if (null? l) - init - (if (null? (cdr l)) - (car l) - (fold-left proc (proc (car l) (car (cdr l))) (cdr (cdr l)))))) - (define (+ . args) (fold-left pair+ 0 args)) @@ -195,6 +209,10 @@ (define (integer? x) (= x (round x))) (define (exact? x) (fixnum? x)) (define (inexact? x) (flonum? x)) +(define (number? x) + (if (fixnum? x) #t + (if (flonum? x) #t + (if (ratnum? x) #t #f)))) ;; LISTS @@ -203,7 +221,7 @@ (define (iter a count) (if (null? a) count - (iter (cdr a) (+ count 1)))) + (iter (cdr a) (fix:+ count 1)))) (iter l 0)) ; Join two lists together @@ -231,19 +249,9 @@ ; let -(define (let-vars args) - (if (null? args) - '() - (cons (caar args) (let-vars (cdr args))))) - -(define (let-inits args) - (if (null? args) - '() - (cons (cadar args) (let-inits (cdr args))))) - (define-macro (let args . body) - `((lambda ,(let-vars args) - ,@body) ,@(let-inits args))) + `((lambda ,(map (lambda (x) (car x)) args) + ,@body) ,@(map (lambda (x) (cadr x)) args))) ; while @@ -257,60 +265,66 @@ ; cond -(define (cond-predicate clause) (car clause)) -(define (cond-actions clause) (cdr clause)) -(define (cond-else-clause? clause) - (eq? (cond-predicate clause) 'else)) - -(define (expand-clauses clauses) - (if (null? clauses) - (none) - (let ((first (car clauses)) - (rest (cdr clauses))) - (if (cond-else-clause? first) - (if (null? rest) - `(begin ,@(cond-actions first)) - (error "else clause isn't last in cond expression.")) - `(if ,(cond-predicate first) - (begin ,@(cond-actions first)) - ,(expand-clauses rest)))))) - -(define-macro (cond . clauses) - (if (null? clauses) - (error "cond requires at least one clause.") - (expand-clauses clauses))) +((lambda () + (define (cond-predicate clause) (car clause)) + (define (cond-actions clause) (cdr clause)) + (define (cond-else-clause? clause) + (eq? (cond-predicate clause) 'else)) + + (define (expand-clauses clauses) + (if (null? clauses) + (none) + (let ((first (car clauses)) + (rest (cdr clauses))) + (if (cond-else-clause? first) + (if (null? rest) + `(begin ,@(cond-actions first)) + (error "else clause isn't last in cond expression.")) + `(if ,(cond-predicate first) + (begin ,@(cond-actions first)) + ,(expand-clauses rest)))))) + + (define-macro (cond . clauses) + (if (null? clauses) + (error "cond requires at least one clause.") + (expand-clauses clauses))) + )) ; and -(define (expand-and-expressions expressions) - (let ((first (car expressions)) - (rest (cdr expressions))) - (if (null? rest) - first - `(if ,first - ,(expand-and-expressions rest) - #f)))) - -(define-macro (and . expressions) - (if (null? expressions) - #t - (expand-and-expressions expressions))) +((lambda () + (define (expand-and-expressions expressions) + (let ((first (car expressions)) + (rest (cdr expressions))) + (if (null? rest) + first + `(if ,first + ,(expand-and-expressions rest) + #f)))) + + (define-macro (and . expressions) + (if (null? expressions) + #t + (expand-and-expressions expressions))) + )) ; or -(define (expand-or-expressions expressions) - (if (null? expressions) - #f - (let ((first (car expressions)) - (rest (cdr expressions)) - (val (gensym))) - `(let ((,val ,first)) - (if ,val - ,val - ,(expand-or-expressions rest)))))) +((lambda () + (define (expand-or-expressions expressions) + (if (null? expressions) + #f + (let ((first (car expressions)) + (rest (cdr expressions)) + (val (gensym))) + `(let ((,val ,first)) + (if ,val + ,val + ,(expand-or-expressions rest)))))) -(define-macro (or . expressions) - (expand-or-expressions expressions)) + (define-macro (or . expressions) + (expand-or-expressions expressions)) + )) ;; TESTING @@ -330,15 +344,42 @@ (define (sum n) (define (sum-iter total count maxcount) - (if (> count maxcount) + (if (fix:> count maxcount) total - (sum-iter (+ total count) (+ count 1) maxcount))) + (sum-iter (fix:+ total count) (fix:+ count 1) maxcount))) (sum-iter 0 1 n)) ; Recursive summation. Use this to compare with tail call ; optimized iterative algorithm. (define (sum-recurse n) - (if (= n 0) + (if (fix:= n 0) 0 - (+ n (sum-recurse (- n 1))))) + (fix:+ n (sum-recurse (fix:- n 1))))) + +;; MISC + +(define (license) + (display +"This program is free software; you can redistribute it and/or modify +it under the terms of the GNU General Public License as published by +the Free Software Foundation; either version 3 of the License, or +(at your option) any later version. + +This program is distributed in the hope that it will be useful, +but WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +GNU General Public License for more details. + +You should have received a copy of the GNU General Public License +along with this program. If not, see http://www.gnu.org/licenses/. +")) + +(define (welcome) + (display +"Welcome to scheme.forth.jl! + +Copyright (C) 2016 Tim Vaughan. +This program comes with ABSOLUTELY NO WARRANTY; for details type '(license)'. +Use Ctrl-D to exit. +"))